1. Field of the Invention
This invention relates to automatic stacking machines in general. In particular, the invention relates to machines for automatically stacking relatively thin, flat objects such as pieces of cloth which are used in constructing garments and the like.
2. Description of the Prior Art
There are various problems with stacking machines used in the garment industry today. Many such machines use gripping devices to place cloth pieces in a stack. Although such machines are effective in forming a stack of cloth pieces, they result in creases, or marks, or other imprints being placed in each individual piece of cloth. Such imprints, of course, may appear in the finished garment. Although pressing may, in some cases, eliminate or reduce the magnitude of such imprints, they are frequently left in the finished garment, thereby detracting from its appearance.
Other stacking machines used in the garment industry permit the pieces of fabric to fall without guidance to a receiving platform or table. The result of this approach is that the individual pieces are not neatly aligned with one another, thereby resulting in an irregular stack. Such an irregular stack makes it difficult to proceed with subsequent automated steps in the manufacture of garments. In order to reduce the degree of the misalignment between the pieces of cloth in such machines, the distance between the conveyor and the receiving platform is limited. As a result, such machines are limited to stacks of cloth no higher than seven inches.
Many present strapping machines use gripping devices to align the fabric with fabric that is already stacked. However, these gripping devices create marks on the fabric which may show up in the final fabric. It would be convenient to be able to align the fabric using a method or apparatus that does not create such marks on the fabric.
U.S Pat. No. 3,370,849, issued on Feb. 27, 1968 to F. C. Martin, discloses a stacking apparatus having a reciprocating table. Martin differs from the present applicant's disclosure in that the fabric in Martin moves from a horizontal conveyor to a system of conveyor belts located at an angle slanting downward from the horizontal conveyor. In Martin, the receiving table itself reciprocates so as to form a stack of folded fabric. By contrast, present applicant's invention is used to stack an unfolded sheet of fabric. A wheel is used in Martin to retain alignment and prevent slippage of the fabric as the fabric is carried frictionally down the slanted conveyor belt system. In the present invention, the wheel serves not only a guiding function but momentarily holds the fabric as a reciprocating carriage, upon which the fabric is moving, changes direction.
It is the object of the present invention to provide an automatic stacking machine which stacks pieces of cloth without the use of means which will grip the pieces and create marks on the fabric, but with the use of wheels to guide and align the fabric as it leaves the reciprocating carriage so as to stack it more efficiently on a stacking table.
It is another object of the present invention to provide an automatic stacking machine of the type having a conveyor and a reciprocating carriage which can stack pieces of fabric which are wider than the conveyor.
It is another object of the present invention to provide a stacking machine with a stacking table of adjustable height.